8048s from Nat Semi

8048s from Nat Semi Following their success in secondsourcing the industry standard 8-bit processor, Intel's 8080, National Semiconductor have now announced versions of what is rapidly turning out to be the industry standard microcomputer, Intel's 8048. A family of parts is to be produced: •

8048 standard Intel specification with 1 kbyte ROM, 64 bytes RAM • 8049 double-ROM/double-RAM 8048 • 8050 a proprietary high density version with 4 kbytes ROM and 256 bytes RAM • 8038, 8039 and 8040 ROMless version of the above three parts All the devices are to be fabricated in XMOS, National's process which they claim will'give a 20-25% reduction in power consumption in full operation (605mW), and consume 12 to 35 times less power in standby mode. Standby voltage is 2.2V which is less than that required for present devices using NMOS technology. 6MHz and 11MHz versions are available with cycle times of 2.5 and 1.3@s respectively. All the devices are designed to be pin for pin replacements of Intel parts, though some extra 'transparent' improvements have been incorporated. In the 8049 the standby current for the onchip RAM is programmable depending on the amount of data memory required,

I~OwlvaTs..~oN

for example: 3, 5, 7 or 9mA is drawn for 32, 64, 96 or 128 words respectively. Also, whereas present devices have only one drive characteristic (100/~A at 2.4 V), National's 8049 has i:hree mask programmable options: • transistor drive 1.5mA at 1.5V • TTL drive 125/~A at 2.4V • open collector - 10/~a maximum Also contained onchip are a battery charging circuit, crystal oscillator capacitors, and a Schmitt trigger with hysteresis.

AMD's "8279' Am279, a programmable keyboard controller, has been designed to work in 8080 and 8085 microprocessor systems. This plug-in compatible replacement for the similar circuit from lntel provides the interface mechanism to control data input and display and, as such, contains both keyboard and display capability. Using the keyboard function, this circuit can interface directly to a standard typewriter-type keyboard or switch. In display mode, it is a drive for alphanumeric displays or a series of indicator lights. The controller has a programmable clock so it can be matched with CPU cycle time. An output interrupt signals the CPU when sensor or keyboard data is available. AdditionallY/, this circuit has 8 bytes of FIFO memory onchip to store keyboard information as well as 16 bytes of RAM for internal display.

lwer..~='r,~-oFrl4e-sE~

L~/STP,EEY, CHI~F & / ~#PUCAl~O~S~ s

J

70~LV so~-n~4Re ~aN/ .~-n4 ~ Po£-c, ercK./ IEDPY 8COTSTRAP IS | I a l~E~zc'f FEC~ u P : ! / " ISCaVl~ over A FIoTI~ ~

~____-----g'l

8086 ICE In-circuit emulation for 8086 processors has now been made available by Intel. This tool provides valuable debugging capability for system development, but at £3954, almost twice the UK 8080 ICE cost, it may frighten off potential users.

SGS-Ates get Z8000 Sole European manufacttJring rights of the Z8000 have been given by Zilog to SGS-Ates. This 16-bit processor will complement their secondsourcing of the Z80. In addition to this, the Company will also supply the ZDS 1/25 and 1/40 development systems and Zilog's single chip microcomputer, the Z8. SGS Ates' rights of distribution with respect to the Z80 have also been expanded now to cover sales in the USA.

Rockwelrs bubbles Boards containing 1 Mbit of Rockwell's bubble memory storage devices are scheduled to become available in the UK this month (May). UK price of the module is £1750 with about another £700 required for a controller to interface to System 65 applications. (More details from Pelco Electronics 0273 722155)

-=f

HEY.,,waFrA ,m,,un~!

k

Ac~e you "rHl~J~l~ ~U~aT/

'~_

~F =--

/'-~tEU..O,~L=Ws I ~ s K . . . Y e s t

l

t'M q]41~r4~tT. ~O~v.., ) ~ CTETo ~ E P~e./ -_--~-~.~ ___._.f/

rb UKe- To 4 ~ a # c ~

% -n4~1- sfuMos ~

~

I t

~oFF-er eP~Att.~'~| ~ u s e R SUPfbRTF ~ m ~ ' I

..

!

•

!, '-L------~.k CA~ STARTI-I~/~JeCoe~,.}L Pft.oB~s -[tlo' ,,. FoR FIAN~-oP~q(Pe--~IBU(E.)~

188

/

I

~ I

i

microprocessors and rnicrosystems